cracking fingers can be observed when one or more finger joints are moved passively (ie by external force) beyond the active range of motion, i.e. the range of motion that is possible through the muscles acting on the joint. Furthermore, the crackling of the fingers can be heard if the joint position is only changed after a long time. The cracking of the finger joints does not cause any pain, and is usually perceived as pleasant or relieving even by those affected. It can be done consciously as well as unconsciously.
Table of Contents
- Causes of cracking fingers
- Glued sliding layers as the reason for cracking fingers
- Symptoms of cracking fingers
- Consequences of finger clicks
- Differential diagnosis
Causes of cracking fingers
Theory I: Are gas bubbles the reason for cracking fingers?
The finger joints, like all “real” joints in the human body, have the same structure. The joint head and socket are enclosed by the joint capsule. The space created in this way is called the joint cavity. The two joint partners are separated from each other by the joint gap. The ligament and the surrounding muscles stabilize the joint.
A distinction is made between basic, middle and end joints in the finger joints. (Image: sebra / fotolia.com)
The joint cavity and the gap are filled with a viscous fluid, the synovia. It increases the lubricity of the articular surfaces and helps to dampen vibrations in the joint. In addition, it transports nutrients into the articular cartilage and contains dissolved gas molecules. If the finger joints are suddenly stretched beyond a certain point, there is a sudden change in the pressure prevailing in the joint. The resulting negative pressure leads to the release of gases dissolved in the synovia. A gas bubble forms, the bursting of which is perceived as a crack. It then takes a moment for the gas concentration in the synovial fluid to rise again, so that it is possible to crack your fingers again.
Glued sliding layers as the reason for cracking fingers
The fascia distortion model (FDM), a model of the emergency doctor and osteopath Dr. Stephen Typaldos DO The word is formed from the Latin terms “fascia” = bundle and “distorsio” = twist. It includes a diagnostic concept that pays special attention to the patient’s body language, clinical appearance and medical history. The treatment then takes place manually.
The model attributes the “crackling noises” to changes in the position and tension of fascia near the joint. In medicine, the term fascia describes a part of the connective tissue that penetrates the human body as a connected network of tension. Fascia play an important role in immune defense and also form the basis for tissue healing processes. Furthermore, fasciae, like the synovia, have the task of absorbing and damping forces (“shock absorber”). Excessively strong pressure or tension, usually in combination with a twisting, leads to deformation and thus to the loss of the ability to reduce vibrations. Pain typically occurs in the further course.
Cracking fingers are attributed to an impairment of the fascia in this model. The partially unconscious cracking of the finger joint is considered as self-therapy, whereby those affected repeatedly independently detach the fascia to relieve the symptoms. Often the actual location of the disturbance is not in the area of the fingers, but rather extends to them. If the fixed region that was identified as the cause is now treated, an improved movement behavior should then appear. The need for self-therapy, i.e. cracking with the fingers, should also no longer be as pronounced.
Cause of finger
clicking clearly clarified at the beginning of 2015, an international team of researchers led by lead author Professor Greg Kawchuk from the Faculty of Rehabilitation Medicine at the University of Alberta (Canada) published a study in the specialist magazine “PLoS One” , which used the phenomenon of finger clicking of MRI scans has finally clarified.
If the finger is pulled sufficiently hard, the joint gap widens and a gas-filled cavity in the synovial fluid (synovial fluid) is created very suddenly. “It’s a bit like a vacuum is building up,” report Professor Kawchuk and colleagues. Because the connection surfaces separate at once, there is not enough liquid available to fill the increasing volume and a cavity is created. The scientists were able to use MRI images to clearly assign the occurrence of the crack to this event, while the bladder regressed silently after the finger was released.
The crackling of the fingers is often provoked. (Image: mraoraor / fotolia.com)
Symptoms of cracking fingers
Cracking fingers appear on both sides of the hands in most cases, but can also be supported on one side. Most sufferers report that the cracking occurs the first time they move after remaining in a flexed or rest position. In other cases, it is provoked by pulling the finger.
As a rule, most people are more disturbed by the noise and there are no additional symptoms. If pain occurs with cracking fingers or severe pain or restricted movement afterwards, a medical examination should be carried out.
Consequences of finger clicks
Since there is currently no evidence-based knowledge about the effects of the resulting forces when the cavity is formed, it cannot be said with certainty whether the finger cracking is harmless. The scientists led by Professor Greg Kawchuk suspect that minimal damage to the bones and joint complaints can actually occur here. In any case, it makes sense to see a doctor as soon as additional complaints such as finger pain or functional restrictions arise.
The repetitive, forced “overstretching” of a joint is a kind of stress for the supporting capsular ligament apparatus, the damage of which goes hand in hand with a loss of the stability of the joint. If this is the case, the distribution of the forces acting in the joint changes and this can lead to disproportionate loading of one or even several joints.
Rubbing noises often occur when there is inflammation of the finger joints. (Image: Africa Studio / fotolia.com)
Differential diagnosis
Pathological movement noises:
“Crunching noises”: Often occurs as a result of advanced, degenerative changes in joints, for example “snowball crunching” as a typical noise for tendon overload damage.
“Rubbing noises”: Often occur as a result of degenerative and inflammatory changes in the joints. Also offer information on damage caused by overloading.
“Snapping noises”: Snapping occurs especially when the joints are unstable. The perceptible noises can be caused by tendons that slide over a bone protrusion.
